Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 315/40-19 | 30/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.92 (734.6) | 30.02 (762.4) | 1.09 (27.8) 3.8% |
| Width inches (mm) | 12.4 (315) | 12.52 (318) | 0.12 (3) 1% |
| Circum. inches (mm) | 90.86 (2307.81) | 94.3 (2395.15) | 3.44 (87.34) 3.8% |
| Sidewall Height inches (mm) | 4.96 (126) | 5.01 (127.2) | 0.05 (1.2) 1% |
| Revolutions per mile (km) | 697.35 (433.31) | 671.92 (417.51) | -25.43 (-15.8) -3.6% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.76 mph (33.41 km/h) |
| 25 mph (40.23 km/h) | 25.95 mph (41.76 km/h) |
| 30 mph (48.28 km/h) | 31.14 mph (50.11 km/h) |
| 35 mph (56.33 km/h) | 36.32 mph (58.46 km/h) |
| 40 mph (64.37 km/h) | 41.51 mph (66.81 km/h) |
| 45 mph (72.42 km/h) | 46.7 mph (75.16 km/h) |
| 50 mph (80.47 km/h) | 51.89 mph (83.51 km/h) |
| 55 mph (88.51 km/h) | 57.08 mph (91.86 km/h) |
| 60 mph (96.56 km/h) | 62.27 mph (100.22 km/h) |
| 65 mph (104.61 km/h) | 67.46 mph (108.57 km/h) |
| 70 mph (112.65 km/h) | 72.65 mph (116.92 km/h) |
| 75 mph (120.7 km/h) | 77.84 mph (125.27 km/h) |
| 80 mph (128.75 km/h) | 83.03 mph (133.62 km/h) |
| 85 mph (136.79 km/h) | 88.22 mph (141.97 km/h) |
| 90 mph (144.84 km/h) | 93.41 mph (150.32 km/h) |
| 95 mph (152.89 km/h) | 98.6 mph (158.67 km/h) |
| 100 mph (160.93 km/h) | 103.78 mph (167.03 km/h) |
| 2.35 | 2.73 | 2.94 | 3.07 | 3.21 | 3.31 | 3.42 | 3.55 | 3.73 | 3.91 | 4.11 | 4.27 | 4.56 | 4.88 | 5.13 | 5.29 | 5.38 | 5.71 | 6.17 | 7.17 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1710 | 1986 | 2139 | 2234 | 2336 | 2408 | 2488 | 2583 | 2714 | 2845 | 2991 | 3107 | 3318 | 3551 | 3733 | 3849 | 3915 | 4155 | 4489 | 5217 |
Better Fuel Economy Factory Ratios Increased Power
